The California Appellate Law Podcast

Best Practices for Expert Testimony

August 29, 2023 Tim Kowal & Jeff Lewis Season 1 Episode 99
The California Appellate Law Podcast
Best Practices for Expert Testimony
Show Notes Transcript

Your next trial could succeed or fail based on whether the expert’s opinion gets admitted or excluded. Based on their recent presentation to financial experts, we cover three key cases—Kelly, Sargon, and Sanchez—that govern expert opinions. We also cover some fundamentals and tips to protect expert work product.

Some things experts should remind their attorneys:

  • “Don’t email me. Pick up the phone instead.”
  • “My opinion is only as good as the facts you’ve told me to base them on.”
  • “Kelly and Sargon are different objections!”
  • “I am a CPA, not Warren Buffet.”
  • Regarding the new amendments to FRE 702: “Expect a tougher fight on admissibility, especially on methodology and reliability of application.”

Appellate Specialist Jeff Lewis' biography, LinkedIn profile, and Twitter feed.

Appellate Specialist Tim Kowal's biography, LinkedIn profile, Twitter feed, and YouTube page.

Sign up for Not To Be Published, Tim Kowal’s weekly legal update, or view his blog of recent cases.

The California Appellate Law Podcast thanks Casetext for sponsoring the podcast. Listeners receive a discount on Casetext Basic Research at The co-hosts, Jeff and Tim, were also invited to try Casetext’s newest technology, CoCounsel, the world’s first AI legal assistant. You can discover CoCounsel for yourself with a demo and free trial at

Other items discussed in the episode:

Announcer  0:03 
Welcome to the California appellate podcast, a discussion of timely trial tips and the latest cases and news coming from the California Court of Appeal, and the California Supreme Court. And now your hosts, Tim Kowal and Jeff Lewis.

Jeff Lewis  0:17 

Welcome, everyone. I am Jeff Lewis.

Tim Kowal  0:19 
And I'm Tim Kowal both Jeff and I are certified appellate specialists and as uncertified podcast co hosts we try to bring our audience of trial and appellate attorneys some legal news and perspectives they can use in their practice. As always, we're grateful if you recommend this podcast to a colleague.

Jeff Lewis  0:34 
Yeah, before we jump into this week's discussion, we want to thank casetext for sponsoring our podcast casetext is a legal technology company that has developed AI back tools to help lawyers practice more efficiently since 2013. Casetext relied on by 10,000 firms nationwide from solo practitioners to amlaw 200 firms and in house legal departments. In March 2023. Casetext launched co counsel, the world's first AI legal assistant, co counsel produces results lawyers can rely on for professional use, all while maintaining security and privacy listeners of our podcast can enjoy a special discount on casetext basic research at That's A L P.

Tim Kowal  1:16 
All right, Jeff. Well, you and I are giving a presentation to a lot of CPA and and financial experts on the subject of best practices for expert testimony. And we've developed this the spectacular outline, Jeff and we thought it would just be wrong to deprive our listenership of the information in this outline. This is disinformation and tips for giving effective expert testimony and getting that testimony admitted into the record at trial from an appellate lawyers perspective. And so we thought that we would share Jim's in this outline with our listenership, Jeff.

Jeff Lewis  1:52 
Yeah, I'm all for double billing in this context.

Tim Kowal  1:56 
There you go. All right. Well, let's jump right into it. Jeff, tell us the overview that we're going to give at this presentation, the overview of of our presentation to financial experts.

Jeff Lewis  2:07  
So we're going to talk about first some preliminary concerns and warnings applicable to the relationship between experts and attorneys. We're going to talk about the hurdles of admissibility of opinions, how to get expert testimony admitted and some of the landmines to look out for you're going to walk our audience through some amendments coming to the Federal Rules of Evidence rule 702. Coming this December, I'm going to talk about production of documents in California, and how recent changes to the law might impact the use of experts. And I'm going to talk about expert testimony and the use of AI. And then you're going to walk the audience through some best tips to protect the privilege and work product doctrine. And then time permitting, we're going to go over some statistics as to what types of opinions are getting excluded from court and for what reason?

Tim Kowal  2:57 
That's right. And the general overview and purpose of this entire presentation is to focus on making sure that an expert's testimony is reliable, admissible and of course understandable to the jury. So let's get right into it. Although we're going to start with some preliminary concerns and warnings. These are things that all trial attorneys and experts need to make sure they have their bases covered on as they set out and start planning their strategy for getting their testimony and their opinions together. The first preliminary concerning morning, assume that everything you discuss with the attorney, this is not we're talking to the experts now assume everything you talk about with your attorney is going to be discoverable. Now, the exception is that if you are retained as an expert for merely consulting and advisory services, not to testify at trial, that is going to be covered under the work product protection, it's not discoverable. But as soon as they're in an there's an intention form, that your opinion is going to be offered at trial, then it becomes discoverable. And you have to plan accordingly. So the takeaway lesson here, if you're the expert, tell your attorney don't email me don't put it in writing, pick up the phone and talk to me instead. There are some exceptions for maybe exchanging draft reports, Jeff, I think that those may still fall under the work product protection, but why why risk it if you can, if you can avoid it, pick up the phone and talk about it. And another question Jeff, maybe you can talk about this. And you need to consider the the expert in the in the attorney need to consider do we really want a written report or are we just going to deliver the the opinion orally at trial? Right?

Jeff Lewis  4:32 
A written report really lays out a outline of an a roadmap of what the opinion is going to be the assumptions for the opinion and can really help your adversary pick it apart so sometimes you want to go into trial with in state court with uh, without a report. I think in federal court, you're required to do written reports when state court you have some flexibility.

Tim Kowal  4:55 

Yeah, if you can get away without doing the written report. All you have to provide in your Expert disclosure is a brief narrative statement of the general substance of the testimony that the expert is expected to give so that the language does not require disclosure of specific facts or opinions. So if you're only going to go in to provide a declaration giving that brief narrative statement, generally what the expert is going to talk about, rather than the opinion itself, then then that requires the other side to pony up and take the experts deposition. All right. And then the third preliminary concern and warning. Are you the expert needed only for rebuttal? Take a look at the dual safety versus superior court case from 2019. Consider waiting to disclose the expert in the rebuttal designation. If you need that expert opinion for the case in chief, then yes, make sure the expert is designated in the expert designation. But maybe they the expert opinion is only needed to rebut the other side's expert in which case maybe hold hold the expert back and wait and see what the other side is going to designate.

Jeff Lewis  6:02 

Yeah, no, that's a great tip. You don't want to make a plaintiff's job easier by allowing them to filling in the holes in terms of experts. All right, in terms of the hurdles of admissibility are what you need to get past to get an expert opinion from an idea in someone's head into presentation before the jury we identified for our presentation. Now later this week, six hurdles of admissibility hurdle one being disclosure that the rules of expert disclosure were followed, that the factual assumptions were supported by an opinion based on factual assumptions that have no support in the record, it can preclude admissibility. Kelly, the Kelly test in terms of the consensus in the relevant scientific or other community Sargon regarding speculative opinions, especially in the area of lost profits, Sanchez, in terms of not relying on hearsay, in connection with opinions. And finally, 352. Undue prejudice, whether or not the contents of the opinion is unduly prejudicial compared to the value, the evidentiary value of the opinion. So that's an overview of the hurdles. And I think we're going to talk individually about each one.

Tim Kowal  7:14
Yeah, yeah. So Jeff, why don't why don't we launch right into the first hurdle? That's where the opinion is not disclosed in discovery? You know, tell us tell us about how to make sure that we don't get opinions excluded for failure to disclose them properly.

Jeff Lewis  7:30 
Well, and, you know, forgetting just the opinion, how about disclosing the experts, you know, there are rules in both state and federal courts in terms of timely disclosing the identity of your expert, what they're going to testify about, and long before their deposition. And then there's a process for a supplemental rebuttal, expert disclosure, and then at the time of deposition, typically, an expert will be asked by a good lawyer, have you now told me about every opinion you intend to offer at trial? And if through that process, the opinion hasn't come out in terms of the earlier disclosures in writing, or the deposition testimony, you're gonna have a very difficult time getting the opinion admitted at trial?

Tim Kowal  8:11 
That's a very important point, be prepared for that question from from counsel. During the deposition. Have you told me all the opinions you're prepared to testify about, make sure you've talked with your attorney, have I covered everything, because I'm going to this is all I'm going to be able to talk about at the deposition, I'm not gonna be able to come out with more, you know, maybe you can get out more if it is just elaborating further on opinions you've already given. But anything that's considered to be a new opinion may be excluded if you haven't provided that. So the purpose of the discovery rules is to give fair notice this is the touchstone of the disclosure rules to give fair notice to the other side of what the expert is going to say at trial so that the opposing party has an opportunity to prepare. So that's the touchstone to be prepared for when the other side is asking you have you told me all the opinions, you need to make sure that you're telling them the opinions in the context of the other side being able to decide, okay, who do we need to get to rebut this? What kind of expert do we need to get to rebut that opinion? And if you haven't given them all your opinions and haven't given them the other the opportunity to decide what other experts what other tools? Do we need to rebut it, then that's fair reason to exclude any opinions that you haven't talked about? Here are some of the grounds that expert opinions may be excluded at trial for for failure to list the witness as an expert that no one's obvious Failure to submit an expert witness declaration. As we said, you have to explain the brief narrative give a brief narrative statement of the general substance of the testimony, failure to produce reports and writings if a report is required, then you have to produce that report. And if you decide not to do a report or disclose a report, then you're going to be limited. The expert is going to be limited to just providing the opinion in writing and not relying on formal reports that were not disclosed in expert discovery and another the final ground for IX cluding as expert opinions, opinions is failure to make the expert available for deposition. So obviously, that expert needs to be prepared to appear at a deposition. And then after the expert deposition, just to kind of close the loop on what we were talking about, Jeff with, may the expert add to or modify the opinions given at the deposition? The answer is no. Generally, the only wiggle room that you may have is that the expert may be able to expand on or explain the opinions at trial, the opinions that were elaborated during the deposition, but be careful that they are not new opinions. So if you find something new that you want to talk about, make sure it's you find a way to link it. So that to the opinions you've already expressed, so that they can be characterized as modified as as explanations rather than new opinions. Right, right. Yeah. Okay, let's move to the next hurdle of admissibility. That's where the experts factual assumptions are not supported. So the rule here is that an opinion based on unsubstantiated and undocumented information is, quote, the antithesis of the scientifically reliable expert opinion. That's admissible under the federal dobbert case, and rule 702. Nothing in either Daubert, or the federal rules requires a district court to admit opinion, evidence that's connected to existing data only by the Ipsy Dixit of the expert. So the expert has to be prepared, not just to say, This is my conclusion, but to explain the methodology and explain the factual assumptions connecting the this case, to the scientifically accepted methodology yielding to the conclusion. Now, you know, once you have the facts that are well supported, and then the methodology that's well supported, it kind of goes through the the black box of the experts, expertise, the experts brain so to speak, but you have to have the facts well established, and you have to have the methodology will support it before you can put it into the experts black box.

Jeff Lewis  12:04 
Yeah, you know, Mike Tyson once famously said, everyone has a plan until they get punched in the mouth. Sometimes when you go to trial, you get punched in the mouth, meaning evidence that you thought was going to come in does, because the witness doesn't show up, or you can't lay the foundation, we've got a judge who had a bad day, and you just can't get the evidence in. And your expert has to be ready to pivot, or you have to have an alternative plan B to get that evidence in. Otherwise, the expert opinions not coming in.

Tim Kowal  12:31 
That's right. That's right. So both the attorney and the expert need to go in to the case with with this maximum in mind that the opinion is only as good as the facts that the expert is basing them on. Because if like you said, Jeff, if you go into that trial, thinking, well, I've got this great opinion. It's well supported by the methodology by the scientific consensus, I'm very confident in it. But then at trial, the the key the linchpin, factual assumption for that expert does not come into evidence or if it's rebutted at trial, then you got big problems, because that opinion is only as good as the factual assumptions. It's based on right. All right, Jeff, the next hurdle, let's talk about people versus Kelly. Yeah, so

Jeff Lewis  13:15 

that's a case from the 1970s. And these days, everybody talks about Sargon Sargon, Sargon Sargon. It's a case about speculation. And people often cite it to try to get expert opinions kicked out. But people V Kelly is a distinct a different way of getting opinions excluded at trial that shouldn't be forgotten. In the context of a scientific opinion, if the expert is testifying outside the general consensus of the relevant scientific community, the expert opinions not going to come in. So it's important in preparing an expert interviewing an expert trying to decide who you're going to designate, is this expert relying on junk science? Or is the methodology generally accepted within the broader community?

Tim Kowal  13:57 

Yeah, that's right. And it is, as you say, Jeff, it is often confused, or seems to be overshadowed by the more recent Sargon case, which deals with speculative opinions. But if you got an opinion, that is that is expressing what I would call an out their opinion, and it's outside the scientific consensus, it may be adhered to by a minority, or maybe it's a minority of one who knows that it's supported by at least one expert, but it may be outside the consensus, and that might not be enough. So if you are, if you're on the other side of an expert, who has got it out there opinion, be prepared to bring a people versus Kelly objection, that the opinion is based out on a methodology outside the scientific consensus. And this issue came up in a case last year in beta versus Johnson and Johnson were involved one of those talcum powder manufacturer cases, the defendants raised Sargon. In this mesothelioma case, the plaintiff recovered a $12 million verdict based in part on plaintiffs experts novel opinion that fibrous talent causes cancer. The defendants argued that, hey, the broader consensus of experts didn't agree with the plaintiffs experts. So the defendant objected on the basis of Sargon that the expert the plaintiff's expert was too speculative. But that was the wrong objection. The Court of Appeal noted that Sargon does not speak to whether a theory is achieved consensus in the field sufficient to render it generally accepted, which is the touchstone and at the defendants wanted to object that the experts opinion was a novel theory that wasn't generally accepted within the scientific community, their motion to exclude did not challenge his testimony based on Kelly and its progeny. So the objection was deemed forfeited. So make sure that if you're in doubt, raise both Sargon and Kelly's the Kelley objection being that the expert opinion is outside the scientific consensus. Yeah, okay. The next hurdle to admissibility of expert opinion, you know, this, this book ends the conversation we're just having about Sargon, this hurdle is that the opinion is too speculative. And that is the Sargon Sargon case.

Jeff Lewis  16:02 
Yeah, in the context of lost profits, there's a big difference between an established company that's been around for decades going to trial and claiming it lost profits, you can go back and look at trends and see where company was headed. And a financial expert could probably do a pretty good job of projecting what those lost profits would have been compare and contrast with somebody who hasn't started a business yet, and in maybe interesting or a newly established industry. That kind of opinion in terms of lost profits for that kind of business can sometimes be speculative. And the Sargon case really reestablished the trial judge's role as gatekeeper keeping out of the jury box crazy speculative opinions that would result in outlandish damages claims.

Tim Kowal  16:49 
Yeah, and I think a lot of folks, the Sargon case is a pretty famous case already by this point. But it involved a the development of a dental implant process and the plaintiff had hired USC to conduct a clinical trial of the process. But USC failed to properly conduct that trial. And the plaintiff argued that well, if I'd only had been conducted, I would have launched into the stratosphere of this dental implant technology and procedure and would have been a hugely profitable business and the expert agreed, and opine that a favorable result of the USC study would have caused 200 dentists to buy 20 More implants each. And the court said, that's not based on anything. That is just it's not based on an analysis of the market. And my takeaway from this, Jeff, to put it in a pithy way is to remember Sargon remember, the expert should remember, I'm a CPA, not Warren Buffett. Okay, no one, no one has any idea other than maybe Warren Buffett, what technology what what business sector is going to take off and in such a stratospheric way, as the expert it'll find in in Sargon.

Jeff Lewis  17:58 
And so we've talked about Kelly, we've talked about Sargon. The third and the trio of cases is in terms of expert admissibility is Sanchez People v. Sanchez, 2016 case coming out of the California Supreme Court, which basically held that hearsay cannot be relied on informing an expert opinion and he can't use as older attorneys have used to do in the good old days use an expert to kind of sneak hearsay into the jurors ears.

Tim Kowal  18:27  
Yeah, that's right. Can't do that anymore after the 2016 people versus Sanchez case.

Jeff Lewis  18:32 
And, yeah, you know, the kind of interesting thing here is, you know, a lot of people, they think something's hearsay. So automatically, an expert can't rely on it or consider it. But there are a ton of exceptions to the hearsay rule. So this topic, if an expert is going to be touching upon potentially hearsay evidence, there should be a discussion with a lawyer about possible exceptions to the hearsay rule, because if there's an exception, Sanchez doesn't apply and they need to come in.

Tim Kowal  18:59  
Yeah, yeah. It goes back to what we said earlier, that the experts opinion has to be grounded in the facts, make sure that the factual assumptions upon which the opinion is based, are supported are going to are supported by evidence that can be admitted, cannot just smuggle in case specific facts through the expert that is going to be hearsay, there is not and never truly has been a an expert exception to the hearsay rule. So there was kind of there's kind of a fiction for a long time that allowed the case specific hearsay to come into the expert, but after the 2016 Sanchez case, cannot expect case specific hearsay to come in through the expert. All right.

Jeff Lewis  19:37 

Yeah, as you say if if an expert's opinion has survived the disclosure rules, and it's all the factual assumption, assumptions have been proven at trial, and it's generally accepted from the scientific community and it survives, the Kelly test and the Sargon test in terms of speculation and Sanchez in terms of hearsay, the last ditch argument to try to keep an opinion out At trial is Evidence Code section 352. Or that the opinion is too prejudicial or that it's prejudicial is substantially outweighed or is not substantially outweighed by the possible relevance or materiality of the opinion to the jury.

Tim Kowal  20:15 
That's right. And attorneys are, obviously we're all familiar with, with the 703 arguments or 352 arguments in state court. So make sure that you're having that conversation with your attorney. This is directed to the experts, the attorney and the expert should be scrutinizing the factual assumptions, making sure that even if they are, they're grounded, they're not here, say you've got a good testimony or good physical evidence, it's going to bring them in, get through the the other rules of evidence if it is too inflammatory, somehow or it is confusing, and it's subject to that 352 or 703. Objection, make sure to scrutinize that and that you're going to be able to get it in. Hopefully, you know, in some of the cases, we're gonna talk about, Jeff, if these issues if you can find a way to get these admissibility issues teed up in a motion eliminated before trial, so you can find out what you're working with before you're in the heat of trial. And that is going to be a big advantage.

Jeff Lewis  21:12 
Yeah, yeah, absolutely. And I do want to reverse it and touch base on a prior subject of Sargon. It is highly relevant the procedural posture of the objection, in terms of Sargon, courts will give much more leeway to an expert. And what's necessary to get testimony admitted at the summary judgment stage than they will be at trial. Because of the rules of liberal construction of evidence at the MSJ stage, a plaintiff is trying to survive an MSJ and has an expert opinion that might otherwise be subject to Sargon at trial doesn't have to necessarily check all the boxes and be airtight at the MSJ stage and might get an expert opinion admitted at the MSJ stage that otherwise wouldn't be admitted at trial. And that's the Michaels V. Greenberg case involved. The trainer Jillian Michaels, if you are dealing with an expert, Sargon issue of the MSJ stage that Michaels cases require greeting,

Tim Kowal  22:09 
remind me, Jeff, be the rule that you're talking about that there's more liberal admissibility rules concerning experts at the MSJ stage, does that apply only to the opposing party's expert? Or can does The expert also get benefit of the liberal rule?

Jeff Lewis  22:25  
So the experts evidence, both the opinion and the factual assumptions giving rise to that opinion, are liberally construed in favor of the person opposing or resisting summary judgment?

Tim Kowal  22:38 

Yeah, that makes sense, again, because of the bias in favor of letting matters go to trial. So the court doesn't want to make the final ruling on admissibility at the MSJ. It's just going to air in the favor of admissibility when it comes to the opposing party's expert,

Jeff Lewis  22:54 

factual list. And I gotta tell you, it will make sense to me in the sense that, at least in California, unlike other states, like Arizona, experts are done last right before trial summary judgment motions are filed months before expert Depositions are taken. So from a practical level, it makes sense that you would give a little more leeway to expert evidence offered in opposition to a motion for summary judgment. I recently had a reason to get involved in a case in Arizona. And I learned that over there, they do things a little differently. Experts are done relatively early in the process and summary judgments are done much later in the process. It's very weird in terms of strategy in terms of disclosure and settlement, things are handled a little differently in Arizona.

Tim Kowal  23:36 

Now that is interesting. Well, you have to be experts, you know who the experts are and what the opinions are, can have an outsized role. So I think if you can manage it, get that get those pieces in place early. Okay, let's So we've covered the six basic hurdles to admissibility of expert opinion. Let's talk a little bit about the new amendments to federal rule of evidence 702. And those amendments, Jeff are practically in effect. Now even though technically, the new rule 702 goes into effect February, rather December 1 of this year 2023. If the supreme court approves the amendments, but the new language commentators observed merely clarify and do not substantively change rule 702 standards about how courts should apply the rule in making admissibility determinations for expert testimony. So here's what the new rule does. It involves the same factors as before. I'll cover those in just a moment. But the new rule 702 confirms that the factors have to be established by a preponderance of evidence. Now, Jeff, when I when I first looked at this, I thought, Well, isn't that obvious? I mean, don't be isn't doesn't the preponderance standard already apply here? Probably, or at least it should have, but there were some courts that that use a little bit more of a sliding scale and maybe they ignored some of the factors and said, Well, we have really strong you know, really strong showing on this one. and other factor and so allowed for admissibility and there was a strong presumption in favor of admissibility. So that presumption in favor of admissibility is going to be gone under the new 702 amendments, right. So the the amendments are going to require more attention to each discrete factor for admissibility outlined under 702. And the courts can no longer use a sliding scale or a presumption in favor of admissibility. So, the factors are first, the opinion has to be helpful to the trier of fact it has to be fact based testimony is based on sufficient facts or data, the opinion has to be based on a reliable methodology. We talked about that before under the the people versus Kelly and it goes to the reliability of the methodology and is it within the scientific consensus or the consensus of other experts in the field? And finally, is the did the expert apply the methodology in a reliable manner linking up the the facts of the case to the methodology to yield a valid and reliable conclusion? Now, this leads to the question, What about the famous dalbert case? dobbert had applied the factors, you know, it didn't change the factors, but the case is following dobbert tended often to improperly apply a pro admissibility gloss and the new amendments of 702. And that pro admissibility gloss. So the upshot on these amendments to rule 702, Jeff, is would be check your methodology, there's going to be no more tie goes to the expert rulings. And experts should be talking with their attorneys about expecting a tougher fight on admissibility under the rules, the new 702 amendments, especially when it comes to the methodology and the reliability of the application because all four of those factors are going to be treated as elements that have to be satisfied under the preponderance of evidence standard.

Jeff Lewis  26:54 
Right. And, you know, this kind of similar to Sargon, reaffirms the role reaffirms the role of the trial judge, as a gatekeeper, especially on this issue of whether the experts opinion reflects a reliable application of the principles and methods to the facts of the case. And I think prior to this amendment, this was viewed as an issue of credibility arguments can be made in front of the jury in terms of going to the weight of the experts opinion. And this rule clarifies that the judge, in terms of its gatekeeping function can decide whether or not the experts application is reliable.

Tim Kowal  27:27
Yeah, yeah. And I think I think often there is a tendency to make the, you know, the threshold determination, is the expert qualified, and will this opinion be helpful to the jury? And then oh, yeah, there's some other stuff. But it's got to be helpful to the jury, and this is a person we trust. So let's just let the opinion in and see how it all shakes out without a lot of and then and then the evidentiary the the factual assumptions will are generally tested during the the crucible of trial to begin with, and if there's objections that come in the court will deal with them. But But I think that that methodology, and the end, the reliability of the application of the methodology, I think are going to be factors to watch now or in to pay more attention to under the amendment. Right, right.

Jeff Lewis  28:10 
Hey, all right. Let's shift gears here and talk about California law, the discovery act as it relates to the production of documents and discovery. We talked in an earlier episode about the Pollak versus superior court case where the court was deciding whether or not a client in a verified discovery response or an attorney or their paralegal can disclose to the other side an index of which documents are being produced or which beats stamps correspond to which document request. You know, in the old days before the law was amended, someone responding to discovery could simply produce a ton of documents, as long as it was organized in the manner in which the business or the person regularly organized their own files. You didn't have to go through the trouble of saying, well, documents seven through 10 relate to request one and documents 20 through 30. Relate to request to this is a new exercise. And we're going to bring this up in our presentation for the experts in the coming days because I rely on experts a great deal and helping me formulate discovery early in a case so that by the time of expert opinions, I've gotten the information that an expert needs to make the opinions and make the opinions admissible. So I think lawyers tend to before this amendment to California law tend to go very broad in terms of document requests, produce all documents that support your case, it's all documents evidence of your damages. And with this new rule regarding having to pinpoint which documents relate to which document request and when you're working with an expert, there's a real incentive now to propound a really narrow document request if it relates to a factual assumption or a fact that your your expert is going to need to rely on. So I'm not a big fan of this new rule as we discussed in a prior podcast, but I think it can be helpful in terms of support Warning, your expert or undercutting your opponents expert by crafting narrow document requests.

Tim Kowal  30:06 
Well, on that subject, Jeff, we're going to talk about this in a minute, just a little bit later. Well, what do you think about this in terms of if you're going to do early discovery, obviously, you want to get as much discovery you can about your case as early as possible. And often, as we just talked about, there's this question of timing of the expert. Do we? Often attorneys don't retain the expert until much later in the case? What do you think about the strategy of retaining the expert early in the case, but only as a consulting or advisory role, not yet as a testifying expert role so that the expert can help advise the attorney what documents to ask for in discovery?

Jeff Lewis  30:40 
Yeah, I, by the way, if you have a client with with means you could do both. You have a consulting expert helping you with the discovery, and the emails and communications you have with that expert need not ever be disclosed. And then you have a second expert who actually is going to testify and give opinions at trial. It's a great strategy. I like to get experts involved as early as I can,

Tim Kowal  31:00 
especially if there are not that many very good experts in a particular niche field. You can lock up more of the experts if you have some of them as a consulting role, and some of them as a testifying role.

Jeff Lewis  31:11 
Yeah, yeah. All right. Let's talk about cutting edge issue experts. And a i, Tim, we've talked a lot in this program about using AI in particular sponsor, co counsel to generate a quick memo on a certain area of law as a as a starting point, or legal research, or if you need a quick opinion for somebody popped into your office. But what about an expert? Do you think an expert should be able to rely on AI or the output of chat GBT? And assessing an opinion? And assessing

Tim Kowal  31:40 
an opinion? Are you talking about a in rebutting an opinion? Or informing the opinion? And

Jeff Lewis  31:46 
sorry, informing their opinion? Yeah, well, in a,

Tim Kowal  31:49 
I can only imagine doing it in the in the same narrow role that you and I may do it as attorneys where we use it to produce research memos to give us some direction about which way the cases are, are pointing. But the opinion I think, has to be the original work product could be expert. Yeah,

Jeff Lewis  32:04 

absolutely. And let me just say this, if you have an expert relying on AI has high probability the opinions gonna get excluded at trial, the if you don't get it excluded at trial, and it's admitted, a jury is going to be told that this expert relied on AI rather than their own thoughts and considerations and the credibility that expert will be severely undermined. So AI is still a developing field. As a general rule, I don't think any expert should be relying on AI today. But you know, more and more cases are talking about AI enhanced tools being admitted. There's a case we'll link to in our show notes called people versus Wakefield. It's a New York case from 2020, to talking about probabilistic genotyping and the use of computer and AI to assist an expert in reaching opinions. And that particular type of work is has gained acceptance in this broader scientific community. So it was held admissible. So there could be a time around the corner where using chat, GBT might be rely might be permissible for an expert to do and might allow for that testimony to be admitted. But I don't think we're quite there yet.

Tim Kowal  33:15 
Jeff, do you know the answer to this question? If the expert were to do some search queries using chat GPT and just kind of hunting and pecking around thinking about some ideas of which direction the opinion might go or trying to get some other ideas for the case? Is that included in the experts file that has to be produced in expert discovery?

Jeff Lewis  33:34 

I would think so the query both the query and the output, I would think would be discoverable. 100% Yeah. Now, I think there are some appropriate uses of AI today. If you get an opposing Experts report, and you need a quick down and dirty analysis of it, there's no harm in running it through chat GBT or another AI tool, just as a starting point for some ideas and how to poke holes. Also, at the conclusion of the experts work, perhaps running an AI report through chat GBT or something else as an independent check against the experts work. That could that might be an acceptable use. Although, if there are inconsistencies between the AI report and the actual Experts report, you might have to disclose that it's part of the discovery process. So maybe that's something the lawyer would do rather than the expert to maintain protection. And then sometimes in the middle of trial, you know, you get punched in the mouth, things change and you need work quick. Perhaps AI can be used to save some time in the middle of trial if you're if you're in a jam, but I generally would not use AI in connection with expert work.

Tim Kowal  34:35 
Yeah, I think that's good advice. Okay. All right. We on to the next subject, Jeff best tips to protect the privilege? Yeah. All right. Well, here's the first tip I alluded to a little bit earlier, and you had me thinking about it more in your discussion of AI Jeff. This is the idea of considering a two phase retainer, a two phase expert retainer, the first phase being a console only retainer, which may allow the expert To more freely discuss and explore ideas for the case, before the attorney and expert decide that the expert is going to be retained to offer opinions testify at trial. And and then the second phase would be the expert witness retainer after, again, the attorney an expert have formed the intention to offer that experts opinion at trial, then obviously, you have to use much more discretion in your communications between the expert and the attorney. Because those are all discoverable. You may want to pick up the phone rather than shooting emails back and forth, which are more easily discoverable and could compromise both the well certainly the the attorneys work product. But on this idea, Jeff, have a console only retainer, if the expert were expert and attorney were interested in exploring ideas, including through using AI, might that be a good opportunity to do it? If the opinion hasn't been formed? yet? We're just kind of spitballing ideas. Maybe you can use AI or whatever the heck else you want to try to get the juices flowing. And I think that would all be covered under work product and would not be discoverable.

Jeff Lewis  36:06 
You know, the contents the query the AI results, yes. But you can always ask an expert at depo. A, in reaching any of your opinions. Did you rely on AI? I think an expert witness would have to at the least say yes or no to that question. And in terms of the next follow up question. I don't know about that.

Tim Kowal  36:25 

Yeah. Well, possibly, I'm just thinking about the in that phase where you haven't formed the opinion quite yet. But once again, and that line can be hard and hard to draw exactly when the opinion was formed. So that's, I think another reason why it's a good idea to create that that retainer agreement at the moment, because I think that would be a nice, clear signpost that this was the moment at which the the opinion was formed and the attention was formed to testify to it at trial, and anything beforehand is not discoverable. So maybe the the expert could look could use that and say, Well, I can only testify, as of you know, march 1 2024. At the time, I entered into the agreement, the intention to offer this testimony this opinion at trial, right? Yeah. Okay. Jeff, tell us about this idea you had about draft opinions and reports using screenshare?

Jeff Lewis  37:15 
Well, I can't say it's my idea. But I've come to learn of some experts who are preparing a report rather than sending you version one, making changes version two, and then making changes in version three. With a paper trail, some experts will just do a screen share with an attorney two or three times. So there's no paper trail. I'm not a big fan of this practice. Because, you know, a savvy lawyer at deposition will ask a witness, you know, did you ever do a screen share? Or how many times did you sit down with the attorney and look over versions of this? There's four change versions, and we don't have a paper trail. So Jerry will never know the evolution of this opinion. What are you hiding, sir? So but I know it is a practice that some experts engage in in terms of using a screen share with a lawyer to avoid multiple iterations of report. I'm not a big fan of it.

Tim Kowal  38:00 

Am I misremembering? Jeff, that if there are prior prior drafts of the expert report that have markups by the attorney, that the markups may be protected under the work product privilege protects don't

Jeff Lewis  38:12 
think it was from me, I'm more concerned about expert iterations not involving the attorneys input.

Tim Kowal  38:17 
Yeah. And and that the expert can be asked to opine or to recollect what those what the input was from the attorney. Yeah, I think the

Jeff Lewis  38:25 
attorneys input remains protected, at least. Yeah, I think so. But it's, it's, I'm talking about pure changes by an expert only, you know, who has an opinion a today and then maybe less than a tomorrow and the road getting from opinion one to opinion two?

Tim Kowal  38:42 
Yeah. Okay. Or what is our next topic? Jeff, are we are we at the recent case examples? Are we going to talk about some of these statistics?

Jeff Lewis  38:51 
Let's talk about the recent cases, I think running late on time here. Okay.

Tim Kowal  38:55 
All right. Well, let's talk about a few of these. Some of these we may have covered previously, but we've we've collected them for this topical episode on expert testimony and whether what kind of opinions get excluded. So here's some recent examples of opinions getting excluded or surviving exclusion. So first, here's an opinion that was excluded. Under Sanchez. The experts opinion of a future a future pain and suffering that was based on talking with other experts was deemed case specific hearsay. That's Townsend versus Ollie VO. It's a June 2021 nonpublic case. But the the issue here was at the expert admitted that he had no knowledge relating to the future procedures and prosthetic devices that the plaintiff had to use. But instead his opinion was based on having spoken with others about the costs involved with those types of products and services and the opinion that his testers opinion he testified about that that was held to be error. It should have been excluded, because that was a Sanchez case. cific hearsay issue. The next case involved with actually all the other cases that we're going to talk about are cases in which the opinion was allowed or the exclusion was reversed on appeal. So here this one is about differential etiology. It's a fancy word for a process of elimination process elimination is a valid method of establishing proximate causation. That was Simon versus regents of University of California. That was a 2022 case and also an unpublished the, the Court held that the process of elimination was valid. It was dealt with an ophthalmologist expert who offered an opinion based on the process of elimination with the trial court had excluded the Court of Appeals said no, that's okay. Here's a tip from an appellate attorney on this case that get the trial court to decide the issue before the trial starts in the Simon case, the issue came up before the trial began leading to a nonsuit for the defense and then the Court of Appeal reverse so at least they don't didn't have to go through the trial twice. Interesting. Okay. Yeah. Okay, here's another one that were the opinion was allowed. A rebuttal expert doesn't have to prove 51% likelihood. I thought this was important because it deals with the difference and important difference between experts and rebuttal experts. This is the Durham cup. Klein versus Zimmer case 2022. This was a published case, this was one of the many lawsuits by hip replacement patients against the maker of the Durham cup of the cases Klein versus Zimmer. It held it the trial court committed structural error when an improperly excluded Zimmers expert to rebut the plaintiffs expert, you'll be exclusion resulted in automatic reversal. So basically the plaintiff offered an expert to apply and that the Durham cup was the cause of the pain and suffering and the defendants expert was going to opine about other possible causes, even if they were not, you know, more likely than not to be the actual cause. And the trial court said, No, it's no good. It has to be established by a preponderance of evidence, you're not even claiming that you think it is, the more likely than not cause and the but the Court of Appeal reversed and said that a defendants expert or the rebuttal expert doesn't have to prove 51% likelihood that 51% threshold is the plaintiffs burden of proof, not the defendants. So this is a important distinction to make. And actually now that now that I'm covering a Jeff, I actually wonder if is this a distinction between the direct expert and the rebuttal expert or is it because it was the defendants expert rather than the plaintiffs expert? And yeah, interesting. I don't know the answer. Yeah. Okay. Next one. Another one where the expert opinion was allowed, despite a Sanchez objection, the expert may also draw from published materials and historical data that was not deemed to be case specific hearsay. This is Strobel versus Johnson and Johnson a 2021. Case in this was in the Johnson and Johnson baby powder legal saga. The trial judge excluded plaintiffs expert witness opinion that Johnson and Johnson's source of talcum powder had traces of asbestos judge had pointed out correctly that the expert actually only looked at Johnson Johnson's talcum sources outside the time period when the plaintiff now having passed away from mesothelioma had been exposed to the product. And instead, the plaintiff had relied on the work of another expert who was not part of the case. And on that basis, he was excluded under Sanchez. But the court ultimately reversed because this case specific hearsay was not the only basis for the plaintiffs experts conclusions, the expert had also drawn upon, quote, various published materials from government agencies and professional standard setting groups published academic articles published reports of historical testing, as well as testing data from their own labs. So I think the the upshot here is, again, make sure you have your bases covered for the factual assumptions that you're giving your expert don't rely on just one thing. It might be, you know, that one thing might be deemed to be, you know, a Sanchez problem. So, you know, have your bases covered, have your expert rely on multiple sources of evidence to establish that underlying fact. Right. Okay, last one, Jeff, this was another final one where the opinion was allowed again, despite Sanchez, an expert, Ken, that was the last one got it. Okay. Yeah.

Jeff Lewis  44:17 
All right. Well, that was super focused discussion about expert testimony. Good refresher on some of the rules governing admissibility of expert testimony. I think that wraps up this episode. Again, we want to thank case tags for sponsoring our podcast each week we include links to the cases we discussed from casetext daily updated database of case law statutes, regulations, codes, and more. And listeners of our podcasts enjoy special discount on casetext basic research a That's

Tim Kowal  44:49 
And if there are other topics that you would like us to cover or guests you'd like us to have on the podcast. Please email us if you know our email addresses, send us directly or info at At cow will reach us and, as always, in our upcoming episodes, look for us to cover more issues about laying the groundwork when preparing for a trial.

Jeff Lewis  45:10 
All right, see you next time.

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